How do I replay Destiny 2 Campaign missions?
Solution 1:
Do campaign missions disappear when I complete them?
Yes, the missions will track on the Director until they're all done.
Where are my quests?
In the Quests tab of the main screen, where you find the Map, Destinations, and Store tabs.
How do I replay the campaigns?
If you go to the Tower and visit Amanda Holliday in the Hanger, she has quests which re-start the campaigns for you.